In sawing chains known heretofore, the individual links have been connected by longitudinal side plates which are riveted together from chain link to chain link. Under this arrangement, if an individual chain link becomes damaged a special tool is required to remove it.
In order to achieve the range of mutual swinging movement of the individual chain links which is required for proper saw operation, a certain play must be allowed between the individual side plates. However this play results in an undesired flexibility of the entire chain in the direction transverse to the common plane of extent and advance (hereinafter, "the operating plane") of the chain. In addition, in the common plane of the individual chain links, said links can flex to form angles in a certain range with respect to each other, with such flexing being in the nature of a kink. Consequently, the links can extend outward to a certain extent, under the action of reaction forces produced by the material being sawed.
Both of the undesired extra movements of the chain links are countered according to prior practice by providing a high chain tension. However, this causes substantially increased running resistance of the entire chain, thereby necessitating a high drive force.
Further, a consequence of the compliance of the chain in the operating plane transverse to the operating plane of the chain is constant contact between parts of the chain and the saw plate which bears them. This necessitates continuous lubrication of the respective contact surfaces, by continuous supply of pressurized oil from a pump, during operation of the saw. Apart from the cost and space requirements of this measure, the continuously supplied oil leads to undesired contamination of the sawdust, which complicates and renders more costly the environmentally benign disposal of said sawdust.
Accordingly, the underlying problem solved by the invention is to devise a saw chain of the type described above, such that excess movement of the chain links is prevented to the maximum extent. At the same time the mobility of the links which is required for proper operation is fully maintained such that individual chain links can be replaced without disturbing the connections of the other links and without the use of special tools.